GB/T 36126-2018Liquefied natural gas dispenser for vehicle (English PDF)

4.1 General

The dispenser shall generally meet.

a) All equipment and piping components in the dispenser which are in contact with LNG shall be of a material that conforms to the LNG cryogenic piping design code.

b) The design pressure of all equipment and piping components in the dispenser shall comply with the relevant requirements of GB 50156.

4.2 Basic functions

4.2.1 Metering and pricing functions

The metering and pricing functions of dispenser shall meet.

a) The dispenser shall have a metering function. The fueling amount of dispenser is measured by mass. The unit of mass is kilograms (kg). The unit of flow is kilograms per minute (kg/min).

b) The dispenser shall have a pricing function. The unit of payment amount is yuan. The unit of unit price is yuan per kilogram (yuan/kg).

4.2.2 Value indication function

The value indication function of dispenser shall meet.

a) The dispenser shall have a value indication function. The indication reading shall be correct, easy to read, and clear.

b) The minimum quality variable of dispenser is expressed as 1×10^n, 2×10^n, or 5×10^n, where n is a positive integer, a negative integer, or zero.

c) When there are more than 2 display indication values, the display of each indication value shall be consistent. The indication value shall be continuously displayed during the fueling process.

4.2.3 Zero return function

4.2.8 Anti-overfill function

In order to prevent the vessel from being overfilled, during the fueling process, the fueling and reclaiming functions of dispenser shall be avoided operating simultaneously.

4.2.9 Auxiliary functions

The auxiliary functions of dispenser include. IC card information reading-writing, data management, and network extension, etc..

4.3 Marking and identification

The marking and identification of dispenser shall meet.

a) The marking and identification of dispenser shall be clear and distinguishable, solid and reliable.

b) There shall be obvious safety and operation identifications on the dispenser.

c) For dispensers with two fueling nozzles and above, the fueling nozzle shall have a corresponding mark.

d) The nameplate of dispenser generally indicates the following. manufacturer's name (trademark), product name and model specification, date of manufacture, exit-factory number, marking and number of license for manufacture of measuring instrument (Note. The new product applicant organization shall reserve a place for the corresponding content on prototype nameplate design), applicable medium, flow range, accuracy level or maximum allowable error, applicable ambient temperature range, maximum working pressure, supply voltage, explosion-proof sign, and explosion-proof conformity certificate number, etc..

4.4 Appearance and structure

The appearance and structure of dispenser shall meet.

a) There shall be no peeling, falling off, rust, etc. on the surface of dispenser.

b) The nameplate and marking of dispenser shall be clear, complete, and accurate.

c) The fasteners of dispenser shall be firmly connected without looseness. The connectors shall be in good contact. […]

4.9 Breakaway protection device

The breakaway protection device of dispenser shall meet.

a) The fueling hose of dispenser shall be equipped with a breakaway protection device, which shall be disconnected into two sections under the rated breakaway force (600 N~900 N).

b) The reclaiming hose of dispenser shall be equipped with a breakaway protection device, which shall be disconnected into two sections under the rated breakaway force (400 N~600 N).

c) The breakaway protection device for larger breakaway force used in special occasions shall be marked with its rated breakaway force on the surface and in the specification.

4.10 Safety protection device

The safety protection device of dispenser shall meet.

a) The dispenser shall be equipped with safety protection devices such as safety valves.

b) Safety protection devices such as safety valves shall obtain the test certificate or identification issued by the safety valve testing agency with corresponding qualifications.

4.11 Power-down protection and re-display functions

The power-down protection and re-display functions of dispenser shall meet.

a) When the dispenser, during the fueling process, interrupts fueling due to power failure, it shall be able to retain all data intact.

b) When the fault occurs, the display time for the current fueling amount and payment amount shall not be less than 30 min. Or within 1 h after the fault occurs, the sum of the time of manual control of single or multiple re-displays shall not be less than 20 min.

4.13.5 Payment amount error

The payment amount displayed on dispenser panel shall not be greater than the calculated payment amount (the product of the unit price and the fueling amount indication value displayed on the panel).

4.14 Environmental adaptability

4.14.1 Low temperature adaptability

The dispenser shall, at a low temperature of -25 °C, be able to work normally. During the test and after the test, within the specified limits, the performance of dispenser is normal. The data shall not be lost. The program or content stored in the memory cannot be changed in any way. The state cannot be changed. The level of each point on all interfaces cannot be abnormally changed.

4.14.2 High temperature adaptability

The dispenser shall, at a high temperature of 55 °C, be able to work normally. During the test and after the test, within the specified limits, the performance of dispenser is normal. The data shall not be lost. The program or content stored in the memory cannot be changed in any way. The state cannot be changed. The level of each point on all interfaces cannot be abnormally changed.

4.14.3 Cyclic damp heat adaptability

The dispenser shall, in a cyclic damp heat environment with a temperature of 25 °C~55 °C and a relative humidity of 93%~95%, be able to work normally. During the test and after the test, within the specified limits, the performance of dispenser is normal. The data shall not be lost. The program or content stored in the memory cannot be changed in any way. The state cannot be changed. The level of each point on all interfaces cannot be abnormally changed.

4.14.4 Power adaptability

The dispenser shall, in the power supply environment with a voltage of 85%~110% of the nominal voltage of the power supply and a supply frequency of (50±1) Hz, be able to work normally. During the test and after the test, within the specified limits, the performance of dispenser is normal. The data shall not be lost. The program or content stored in the memory cannot be changed in any way. The state cannot be changed. The level of each point on all interfaces cannot be abnormally changed.

4.14.5 Electrostatic discharge immunity

4.16 Durability

After the durability test, the maximum allowable error and repeatability of dispenser shall comply with the requirements of 4.13.1 and 4.13.2. The variation of indication error, compared with that before the test, shall not exceed 0.5%.

4.17 Transportation adaptability

Under the conditions of packaging and transportation, the dispenser, after the transportation adaptability test, shall meet the requirements of 4.2 and 4.13.

4.18 Key components

4.18.1 Cryogenic flowmeter

The cryogenic flowmeter shall meet.

a) The cryogenic flowmeter used in dispenser shall have a clear nameplate and complete identification. The metering accuracy level shall not be lower than level 0.5.

b) The flow range, temperature range, pressure range, and medium used of cryogenic flowmeter shall meet the technical requirements of dispenser.

c) The cryogenic flowmeter shall obtain the license for manufacture of measuring instrument and explosion-proof conformity certificate.

d) The dispenser for trade settlement shall be equipped with a liquid phase flowmeter for measuring the fueling amount and a gas phase flowmeter for measuring the reclaiming amount.

4.18.2 Electronic computer

The electronic computer shall have an indication function, a zero return function, an error adjustment function, and a payment amount indication function, etc..

5.1 Basic functions

According to the requirements of 4.2, the basic functions of dispenser are checked by visual and conventional methods. […]

5.11 Electrical safety performance

Electrical safety performance tests shall be carried out in accordance with the following requirements.

a) According to the requirements of 4.12, by the method of GB 4943.1, the earth leakage current of dispenser is tested.

b) According to the requirements of 4.12, by the method of GB 4943.1, the dielectric strength of dispenser is tested.

c) According to the requirements of 4.12, by the method of GB 4943.1, the connecting resistance between the grounding terminal or grounding contact of dispenser and the component to be grounded is tested.

d) According to the requirements of 4.12, by the method of GB 4943.1, the corrosion resistance of grounding terminal of dispenser and the conductive components in contact with the connection end is tested.

5.12 Metering performance

5.12.1 Test medium

The metering performance test, according to the provisions of GJB 2253A, uses liquid nitrogen as the test medium.

5.12.2 Test equipment

The metering performance test uses cryogenic liquids flow standard facilities by weighing method (SEE Appendix B), also can use cryogenic liquids flow standard facilities by master meter method (verification facilities for LNG dispenser, hereinafter known as verification facilities for short, SEE Appendix C).

5.12.3 Test methods

5.12.3.1 Test flow point and number of tests

The test flow points are selected as shown in Table 1. […]

5.13 Environmental adaptability

5.13.1 Low temperature adaptability

According to the severity in temperature lower limit test of GB/T 2423.1. temperature -25 °C, continuous standing time 2 h, recovery time 2 h, the test is conducted. After the test, according to the requirements of 4.14.1, the dispenser is checked.

5.13.2 High temperature adaptability

According to the severity in temperature upper limit test of GB/T 2423.2. temperature 55 °C, continuous standing time 2 h, recovery time 2 h, the test is conducted. After the test, according to the requirements of 4.14.2, the dispenser is checked.

5.13.3 Cyclic damp heat adaptability

According to the severity in GB/T 2423.4. upper limit of temperature 55 °C, lower limit of temperature 25 °C, relative humidity 93%~95%, 24 h cycle, the test is carried out. After the test, according to the requirements of 4.14.3, the dispenser is checked.

5.13.4 Power adaptability

According to the combinations of Table 2, the power adaptability test is carried out. After the test, according to the requirements of 4.14.4, the dispenser is checked.

B.1 Expanded uncertainty

The expanded uncertainty (coverage factor k=2) of the indication error measurement result of cryogenic liquids flow standard facilities by weighing method shall not exceed 1/3 of the absolute value of the maximum allowable error of dispenser.

B.2 Standard facilities

The main standard is an electronic balance, which shall be equipped with a verification certificate within the validity period.

B.3 Ancillary equipment

B.3.1 Vessel

The technical specifications of the vessel shall meet the requirements of GB/T 18442.1. It shall be equipped with a test certificate within the validity period.

Before the test, the maximum filling capacity of the vessel shall be calculated and shall not exceed 90% of the nominal volume of the vessel.

B.3.2 Standard weight

The standard weight shall not be lower than the F2 level. Its mass shall be between 80%~100% of the maximum weighing value.

B.3.3 Piping and valves

Piping and valves, etc. for storage and flow of liquid nitrogen shall comply with cryogenic piping design code. […]